数据库：mysql
表名：info
字段：url
url中存放的是域名信息：比如
www.baidu.com
www.
news.
www.
bbb.
aaa.
我想查询 哪个域名出现的次数最多，并且进行排序。
结果如下：
3次
2次
1次

select url,count(url) from info
group by url
order by count(url) desc;

select substring(url,charindex('.',url)+1,20),count(substring(url,charindex('.',url)+1,20)) from test group by substring(url,charindex('.',url)+1,20)

忘了排序,
select count(substring(url,charindex('.',url)+1,20)),substring(url,charindex('.',url)+1,20)
from test group by substring(url,charindex('.',url)+1,20)
order by count(substring(url,charindex('.',url)+1,20)) desc

select url,count(url) from info
group by url
order by count(url) desc;